What is the pH of a solution with a concentration of 7.6 × 10–7 M H3O+?

0.993
6.12
7.88
8.34

Answer:

The student measured the cup and got an incorrect answer

Explanation:

because he was in a rush.

The given question is incomplete. The complete question is:

When 282. g of glycine (C2H5NO2) are dissolved in 950. g of a certain mystery liquid X, the freezing point of the solution is 8.2C lower than the freezing point of pure X. On the other hand, when 282. g of ammonium chloride are dissolved in the same mass of X, the freezing point of the solution is 20.0C lower than the freezing point of pure X. Calculate the van't Hoff factor for ammonium chloride in X.

Answer:  the van't Hoff factor for ammonium chloride is 1.74

Explanation:

Depression in freezing point is given by:

[tex]\Delta T_f=i\times K_f\times m[/tex]

[tex]\Delta T_f=T_f^0-T_f=8.2^0C[/tex] = Depression in freezing point  

[tex]K_f[/tex] = freezing point constant = ?

i = 1 ( for non electrolyte)

m= molality

[tex]8.2^0C=1\times K_f\times \frac{\text{mass of solute}}{\text{molar mass of solute}\times \text{weight of solvent in kg}}[/tex]

Weight of solvent (X)= 950 g = 0.95 kg

Molar mass of solute (glycine) = 75.07 g/mol

Mass of solute (glycine) = 282 g

[tex]8.2^0C=1\times K_f\times \frac{282g}{75.07g/mol\times 0.95kg}[/tex]

[tex]K_f=2.07[/tex]

ii) [tex]20.0^0C=i\times \times \frac{\text{mass of solute}}{\text{molar mass of solute}\times \text{weight of solvent in kg}}[/tex]

Weight of solvent (X)= 950 g = 0.95 kg

Molar mass of solute (ammonium chloride) = 53.49 g/mol

Mass of solute (ammonium chloride) = 282 g

[tex]20.0^0C=i\times 2.07\times \frac{282g}{53.49g/mol\times 0.95kg}[/tex]

[tex]i=1.74[/tex]

Thus the van't Hoff factor for ammonium chloride is 1.74

Answer:

34.44 kg

Explanation:

First we convert 1.00 kg of phosphorus (P) into moles, using its molar mass:

Then we convert 0.03125 kmoles of P into kmoles of Ca₃(PO₄)₂:

Now we calculate the mass of 0.0625 kmoles of Ca₃(PO₄)₂:

Finally we calculate the required mass of the ore, using the definition of content percentage:

Answer: An object's gravitational force depends primarily on the object's mass.

Explanation:

According to the Universal law of gravitation, every object whether is it is having large r small mass tends to exert a force on every other object, therefore this force is known as gravitational force.

Formula to calculate gravitational force is as follows.

[tex]F = \frac{G \times m_{1} \times m_{2}}{r^{2}}[/tex]

where,

F = Gravitational force

G = Gravitational constant = [tex]6.674 \times 10^{-11} m^{3}/kg s^{2}[/tex]

[tex]m_{1}[/tex] = mass of object 1

[tex]m_{2}[/tex] = mass of object 2

r = distance between the centers of the objects

Therefore, it means that gravitational force of an object primarily depends on an object's mass.

Thus, we can conclude that an object's gravitational force depends primarily on the object's mass.

Answer:

and is capillaries

Explanation:

hope it helps

Answer:

hi which language is this???

I can't understand

Answer:

Filipino hello pari omsim

Answer:

1. 1.33 gram of carbon

2. 2.38g of carbon dioxide

Explanation:

From the given information:

Total amount of CO₂ = 4.86 grams

Atomic mass of C = 12 g/mole

molar mass of CO₂ = 44 g/mole

∴

The mass of the Carbon (C) in grams is:

[tex]= Total\ amount \ of \ CO_2 \times \dfrac{12 \ g/mol}{44 \ g/mol}[/tex]

[tex]= 4.86 \ g \times \dfrac{12 \ g/mol}{44 \ g/mol}[/tex]

= 1.33 gram of carbon

2.

Here, the total amount of CO₂ = unknown

Atomic mass of O₂ = 32 g/mole

molar mass of CO₂ = 44 g/mole

amount of oxygen = 1.73 g

∴

The mass of CO₂ = [tex]Total \ amount \ of \ O_2 \times \dfrac{44 \ g/mol}{32\ g/mol}[/tex]

[tex]=1.73 \times \dfrac{44 \ g/mol}{32\ g/mol}[/tex]

= 2.38 g of carbon dioxide

Answer:

Match up correct answers:

1) trigonal planar

2) tetrahedral

3) trigonal pyramid

4) linear

Explanation:

(correct answers on portal and edmentum users)

Hope I was helpful, have a great day and good luck :)

AlH₃ - trigonal planar

CH₂F₂ - tetrahedral

PH₃ - trigonal pyramidal

O₃ - bent

The valence shell electrons in a molecule are depicted in an extremely simplified manner by a Lewis Structure. It is used to demonstrate how the electrons in a molecule are positioned around particular atoms. Electrons are shown as dots or, in the case of a bond, as a line connecting the two atoms.

Learn more about molecular geometry here:

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Answer:

Explanation:

Its a chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the air. These substances  rise  high into the atmosphere in which they mix and react with water, oxygen, and other chemicals to form more acidic pollutants.

Answer:

Explanation:

Acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the air. These substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain.

Answer:

I don't get it

Explanation:

please explain more about question

Explanation:

Depression in Freezing point

= Kf × i × m

where m is molality , i is Van't Hoff factor, m = molality

Since molality and Kf remain the same

depression in freezing point is proportional to i

i= 2 for CuSO4 ( CuSO4----------> Cu+2 + SO4-2

i=1 for C2h6O

i= 3 for MgCl2 ( MgCl2--------> Mg+2+ 2Cl-)

So the freezing point depression is highest for MgCl2 and lowest for C2H6O

so freezing point of the solution = freezing point of pure solvent- freezing point depression

since MgCl2 has got highest freezing point depression it will have loweest freezing point and C2H6O will have highest freezing point

Answer:

True

Explanation:

The tertiary structure of a protein is a complex arrangement formed as the polypeptide chain folds and twists.

This folding & twisting of polypeptide chain leading to its complex structure, is true about tertiary structure of protein. It occurs due to different interactions between side chains of amino acids.

Answer:

Inversely

Explanation:

The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object.

Answer:

a. True

Explanation:

Magnesium nitride, Mg₃N, is a binary salt. Upon heating, it decomposes into magnesium metal and nitrogen gas. The unbalanced equation is:

Mg₃N(s) ⇒ Mg(s) + N₂(g)

We can balance it with the trial and error method. First, we will balance N atoms by multiplying Mg₃N by 2.

2 Mg₃N(s) ⇒ Mg(s) + N₂(g)

Then, we get the balanced equation by multiplying Mg by 6.

2 Mg₃N(s) ⇒ 6 Mg(s) + N₂(g)

Answer:

101.6ml

Explanation:

Using the formula;

CaVa = CbVb

Where;

Ca = concentration of acid (M)

Cb = concentration of base (M)

Va = volume of acid (ml)

Vb = volume of base (ml)

Based on the information as follows:

Ca = 2.5M

Cb = 1.23M

Va = 50ml

Vb = ?

Using CaVa = CbVb

2.5 × 50 = 1.23 × Vb

125 = 1.23Vb

Vb = 125/1.23

Vb = 101.6ml

Answer:

O D. 4

Explanation:

A carbon atom is an element that can be found in the atomic number 6th of the periodic table. It electronic configuration is 1s² 2s² 2p². It is a tetravalent and non metallic compound. In its outermost structure, Carbon needs four additional valence electrons to complete its octet structure. That is why hydrogen with only one electron can be bonded to one carbon atom in four different places making the carbon element obtain a tetrahedral shape.

Answer:

4.7 atm

Explanation:

From the question given above, the following data were obtained:

Total pressure (P) = 15.3 atm

Pressure of Helium, P(He) = 3.2 atm

Pressure of Oxygen, P(O) = 7.4 atm

Pressure of Argon, P(Ar) =?

The pressure of Argon, P(Ar) in the tank can be obtained as illustrated below:

P = P(He) + P(O) + P(Ar)

15.3 = 3.2 + 7.4 + P(Ar)

15.3 = 10.6 + P(Ar)

Collect like terms

15.3 – 10.6 = P(Ar)

4.7 = P(Ar)

P(Ar) = 4.7 atm

Therefore, the pressure of Argon, P(Ar) in the tank is 4.7 atm

The correct answer is

C. -1108.7 kJ/mol rxn

From the table values, the standard Gibbs free energy change for the formation of POCl₃ is -1108.7 kJ/mol

We can calculate ΔG° for the reaction using the following formula:

ΔG° = ΣnΔG°f(products) - ΣnΔG°f(reactants)

where ΔG°f is the standard Gibbs free energy of formation for each compound and n is the stoichiometric coefficient of each compound in the balanced chemical equation.

We can look up the values of ΔG°f for each compound in tables of thermodynamic data. At standard conditions (25°C and 1 atm pressure), the values are:

ΔG°f (POCl₃) = -558.9 kJ/mol

ΔG°f (P₂) = 0 kJ/mol

ΔG°f (O₂) = 0 kJ/mol

ΔG°f (Cl₂) = 0 kJ/mol

Plugging these values into the formula, we get:

ΔG° = (2 mol)(-558.9 kJ/mol) - (1 mol)(0 kJ/mol) - (1 mol)(0 kJ/mol) - (3 mol)(0 kJ/mol)

ΔG° = -1117.8 kJ/mol

Therefore, the correct option  is C. -1108.7 kJ/molrxn. Note that this answer differs slightly from the calculated value because the given choices are rounded to one decimal place.

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Answer:

7.03 g

Explanation:

Step 1: Write the balanced synthesis reaction

N₂(g) + 3 H₂(g) ⇒ 2 NH₃(g)

Step 2: Calculate the moles corresponding to 32.5 g of N₂

The molar mass of N₂ is 28.01 g/mol.

32.5 g × 1 mol/28.01 g = 1.16 mol

Step 3: Calculate the number of moles of H₂ needed to react with 1.16 moles of N₂

The molar ratio of N₂ to H₂ is 1:3. The moles of H₂ needed are 3/1 × 1.16 mol = 3.48 mol.

Step 4: Calculate the mass corresponding to 3.48 moles of H₂

The molar mass of H₂ is 2.02 g/mol.

3.48 mol × 2.02 g/mol = 7.03 g

Answer:

false it's more than two

Answer:

A crack in earth's crust is called a fault also known as a "fracture"

Answer:

True! A transverse wave does move a medium at an obtuse angle to the wave!!

Answer:

False

Explanation:

Answer. Chemical formula of ghee: (C17H33 Coo)3 C3H5 • Chemical Reaction: (C17H31Coo)3 C3H5 + 3H2 (C17H33 Coo)3 C3H5

Answer:B

Explanation: Pennfoster answer

Answer:

81 gm

Explanation:

The mass of 1 mole is 27 gSo, Mass of 3 moles of Aluminium would be 3 × 27 = 81 gm

Thus mass of 3 Moles of Aluminium is 81 gm.

Answer:

25.1 g

Explanation:

Step 1: Write the balanced decomposition reaction

2 HBr(aq) ⇒ H₂(g) + Br₂(l)

Step 2: Calculate the moles corresponding to 24.7 g of Br₂

The molar mass of Br₂ is 159.81 g/mol.

24.7 g × 1 mol/159.81 g = 0.155 mol

Step 3: Calculate the moles of HBr needed to produce 0.155 moles of Br₂

The molar ratio of HBr to Br₂ is 2:1. The moles of HBr needed are 2/1 × 0.155 mol = 0.310 mol.

Step 4: Calculate the mass corresponding to 0.310 moles of HBr

The molar mass of HBr is 80.91 g/mol.

0.310 mol × 80.91 g/mol = 25.1 g